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Nonverbal behavior of the type A individual.

Forty-one health professional students were videotaped during three consecutive conditions: a 5-min wait for a tardy interviewer, the structured interview for determining the Type A behavior pattern, and a 5-min relaxation period. Afterward, subjects were classified as Type A or B based on audiotapes of the interview. The total amount of activity and the frequency or duration of Type A behaviors were compared between Type A and Type B subjects. In all three experimental conditions, Type A subjects moved their arms more than Type B subjects. During both the waiting and the relaxation periods, Type A subjects sat still less and spent more time exploring than did Type B subjects. During the interview, Type A subjects gestured more frequently than Type B subjects. Nonverbal behaviors correctly identified behavior pattern in 71% of the subjects. The addition of nonverbal behaviors improved the discrimination of behavior pattern above that obtained from verbal behavior alone. The greater activity, restlessness, exploratory behavior, and gestures of Type A persons are consistent with the two major etiologies proposed for the Type A behavior pattern.

Adult↗

Altered psychomotor behaviors in mice lacking pituitary adenylate cyclase-activating polypeptide (PACAP).

Pituitary adenylate cyclase-activating polypeptide (PACAP) has been conserved remarkably during evolution and is widely expressed in the mammalian brain. In Drosophila, mutation of the PACAP homologue results in behavioral defects, including impaired olfaction-associated learning and changes in ethanol sensitivity. Here, we report the generation of mice lacking the PACAP gene (PACAP(-/-)). PACAP(-/-) mice were born in the expected Mendelian ratios but had a high early-mortality rate. The surviving adult PACAP(-/-) mice displayed remarkable behavioral changes; they exhibited hyperactive and explosive jumping behaviors in an open field, increased exploratory behavior, and less anxiety in the elevated plus maze, emergence, and novel-object tests. Analysis of PACAP(-/-) mice brains revealed that the serotonin metabolite 5-hydroxyindoleacetic acid was slightly decreased in the cortex and striatum compared with wild-type mice. The present study provides evidence that PACAP plays a previously uncharacterized role in the regulation of psychomotor behaviors.

Animals↗

L-Dopa repairs deficits in locomotor and investigatory exploration produced by denervation of catecholamine terminal fields in the forebrain of rats.

In a previous study rats were shown to have decreased locomotor and investigatory exploration after bilateral microinjections of 6-hydroxydopamine into the anterolateral hypothalamus. These deficits correlate with the loss of catecholamine terminals in neocortical, limbic, and anteromedioventral striatal brain sites. To test whether this correlation was causal, central catecholamines were increased by the intraperitoneal administration of L-3,4-dihydroxyphenylalanine (L-dopa), 10--40 mg/kg) after inhibition of extracerebral L-amino acid decarboxylase. Such treatment repaired the deficits in locomotor exploration and investigation in 6-hydroxydopamine rats. Pretreatment with the catecholamine antagonist chlorpromazine (1--2 mg/kg) blocked the increase in locomotor exploration and investigation produced by L-dopa in 6-hydroxydopamine rats. The results suggest, but do not prove, that L-dopa produced these behavioral effects by increasing central catecholamines at the denervated catecholamine receptor sites in the forebrain. These data and the data from the previous study are complementary evidence for the hypothesis that forebrain catecholamine synaptic action is necessary for normal exploratory behavior.

Animals↗

A novel open field activity detector to determine spatial and temporal movement of laboratory animals after injury and disease.

The wide range of tests for laboratory animal behavior after neurological injury or disease each have their benefits and detriments. The varied behavior an animal exhibits makes it difficult to decide which test to use. However, a fundamental instinct for the laboratory animal is to explore when placed in a new environment. A way to test exploratory behavior is in the open field. Here, we introduce a simple activity box without the use of video equipment to determine the exploratory movement of a rat after traumatic brain injury. The activity box is an open field and the rat explores its surroundings when placed inside. Four infrared beams were placed in both the X and Y-axis inside the box. Using a novel system to determine which beam the rat breaks, we describe where the rat is in space and time while in the activity box. Other models can show the number of beams broken, but here we elucidate the methods to additionally determine the amount of area explored, the total distance traveled by the rat and percent time exploring.

Animals↗

Behavior of immature and middle-aged mice as a function of dietary protein.

The differential effects of continued maintenance on a 12% vs. 24% protein diet were examined in immature and middle-aged male and female C57BL/6J mice. Exploratory behavior, body weight and fluid consumption of water, saccharin and quinine were monitored over 9 weeks of presentation of the special diets. No rehabilitation datawere obtained. The dietary manipulations differentially effected the various groups, but the pattern of change in behavior was a function of the age and sex of the subject and the specific measure employed.

Age Factors↗

Parameters of cell immune response in Wistar and OXYS rats and their behavior in the open field test.

Comparative analysis of the state of the thymus, activity of cell component of the immune system, and open field behavior of Wistar and OXYS rats showed early involution of the thymus in OXYS rats. By morphological picture this involution corresponded to accidental involution and was paralleled by low level of delayed hypersensitivity reaction and by inhibition of motor and exploratory behavior.

Animals↗

Early stimulation effects on novelty-induced behavior in two psychogenetically-selected rat lines with divergent emotionality profiles.

The present study shows that postnatal handling (H: consisting of removing the pups from the nest twice daily and placing them individually in plastic cages lined with paper towel for a period of 10 min, between postnatal days 1 and 21) and/or environmental enrichment (E: for a period of 6 months) of Roman high- and low-avoidance (RHA/Verh and RLA/Verh) rats induced long-lasting decreases in emotional reactivity (i.e. reduced defecations in the open field, OF, and hole-board, HB, tests) as well as increases in exploratory behavior (i.e. head-dipping) in a manner dependent upon the rat line (there were 'line x H' and 'line x E' interactions). It is reported for the first time that RHA/Verh rats show more head-dipping behavior than RLA/Verh rats, and that the environmental treatments can increase head-dipping of RLA/Verh animals to the level shown by RHA/Verh rats.

Animals↗

Some behavioral effects of AMPA/kainate receptor agonist and antagonists.

The effects of an agonist (S-AMPA, i.c.v.), as well as competitive (CNQX, NBQX, DNQX, i.p.), and noncompetitive antagonists (GYKI 52466, i.p.) at the AMPA/kainate receptors were examined in the open field and the Vogel tests of anxiety. It was found that both kinds of antagonists inhibited rat exploratory behavior in a dose-dependent manner, at the dose range exhibiting a clear-cut tendency to decrease rat locomotor activity. They appeared inactive in the Vogel test over an examined dose-range. S-AMPA, whereas not changing in a significant way rat behavior in the open field, significantly enhanced the suppressive influence of a shock on drinking in the Vogel test. The drug administered at the dose of 2 micrograms/5 microliters, i.c.v., revealed also a tendency to decrease the motor activity followed by prodromal symptoms of epileptic-like activity in some subjects. It is concluded that AMPA/kainate receptors probably are not directly involved in the control of rat emotional behavior. Thus, their primary role as putative neuroprotective and anticonvulsant agents is indirectly confirmed.

6-Cyano-7-nitroquinoxaline-2,3-dione↗

Fibroblast growth factor-18 reduced infarct volumes and behavioral deficits after transient occlusion of the middle cerebral artery in rats.

BACKGROUND AND PURPOSE: Fibroblast growth factor 18 (FGF18) is expressed in rodent brain and is a trophic factor for neuron-derived cells in culture. The purpose of the present study was to evaluate whether FGF18 was neuroprotective in a rat model of cerebral ischemia and to compare the results with those obtained with FGF2. METHODS: Cerebral ischemia was produced in rats by a transient 2-hour occlusion of the middle cerebral artery (MCAo) with an intraluminal filament followed by 22-hour reperfusion. Starting 15 minutes after MCAo, FGF18 or FGF2 was administered by a 3-hour intravenous infusion. Infarct volumes and behavioral deficits were measured 24 hours after MCAo. RESULTS: Infusion of FGF18 produced dose-dependent reductions in infarct volumes and improvements in tests of reference and working memory, motor ability, and exploratory behavior. FGF18 was more efficacious than FGF2 on virtually all measures examined. The reductions in infarct volume and behavioral deficit were associated with FGF-mediated increases in regional cerebral blood flow. CONCLUSIONS: These results demonstrate that FGF18 is an effective neuroprotective agent in a rat model of transient MCAo.

Animals↗

Harm avoidance, anxiety, and response to novelty in the adolescent S-100beta transgenic mouse: role of serotonin and relevance to Down syndrome.

S-100beta is an astroglial-derived protein, which plays a role in brain development and maintenance, and is known to play a specific role in the regulation of growth of the serotonergic neuronal system. In humans, the gene for S-100beta is found on chromosome 21, within the region that is considered important for the phenotype of Down syndrome (DS). Thus, we have been studying a model of DS, the S-100beta transgenic mouse. In the current study, we have examined anxiety and responses to novelty in adolescent (60-90 days) animals, at a time when we have shown the animals to be relatively lacking in serotonin innervation, compared to their CD-1 nontransgenic controls. In a test for approach/avoidance, the light/dark test, the S-100beta transgenic mice animals showed no differences from control CD-1 mice. However, in the hole-board test for exploratory behavior, the S-100beta animals were found to be less responsive to the inhibiting effects of the serotonin receptor 5-HT1A agonist, buspirone. Three tests were used to measure response to novelty. In the open field, the S-100beta animals showed greater activity longer than the control animals, and in the Y-maze test, the S-100beta animals spent more time in the novel arm. In a test for novelty-induced gnawing, the S-100beta animals were also more active than control animals. All of these suggest that the S-100beta transgenic mice are slower to habituate to novelty than control animals. Finally, we tested the animals in a new procedure that we are proposing as a test for harm avoidance. In this apparatus, the S-100beta animals showed more approaches to a novel and potentially harmful object than the control mice did. These results are discussed in reference to the known lack of serotonin in the animals, and to the behavioral phenotype of DS.

Animals↗

Factor analysis of spatiotemporal and ethological measures in the murine elevated plus-maze test of anxiety.

Recent research employing the elevated plus-maze to assess anxiety in rodents has incorporated a variety of behavioral elements in addition to the standard parameters of entries onto and time spent in the aversive open arms. In the present study, we have used a large database comprising the behavioral profiles of 90 undrugged mice to examine the relationship between the standard spatiotemporal measures and a range of specific behaviors related to the defensive repertoire of the mouse. A factor analysis applied to the standard measures revealed two factors related to anxiety and locomotor activity. The simple addition of center time (an infrequently recorded measure) to the analysis yielded a third factor, most probably related to decision making. A large-scale factor analysis applied to all measures further confirmed the existence of factors related to anxiety, locomotor activity, and decision making, and revealed three further factors thought to represent risk assessment, vertical activity, and exploratory behavior. Thus, the inclusion of ethological measures not only confirmed prior knowledge based on a very limited range of measures, but also demonstrated the existence of additional behavioral dimensions. The potential applications of this knowledge are discussed.

Animals↗

Chronic administration of SCH 23390 enhances spontaneous searching and locomotor activity of rats. An open field study.

The influence of dopamine D1 receptor supersensitivity, induced by repeated SCH 23390 administration, on rat spontaneous behavior was studied in an open field test. The frequency of line crossing, rearing and looking-into-holes episodes was evaluated as a part of the locomotor and exploratory behavior. SCH 23390 was injected subcutaneously in a dose of 0.5 mg/kg, one injection per day for 21 days. Controls were injected with isotonic saline. When the open field test was applied one day after the last treatment, all the tested parameters were significantly enhanced in rats treated repeatedly with SCH 23390. The effects were diminished after 3 days and had almost disappeared after 7 days. It is argued that supersensitivity of dopamine D1 receptors is responsible for the increase in locomotion and exploration.

Animals↗

Behavioral responses to novelty and structural variation of the hippocampus in mice. II. Multivariate genetic analysis.

On the basis of results from lesion studies in rodents, covariations are expected to exist between naturally-occurring heritable variations in hippocampal morphology and exploratory behavior elicited by novel surroundings. For this reason, we set up a full diallel cross between five inbred mouse strains and analyzed the behavioral and the hippocampal anatomical variation in male animals from this cross. Employing a bivariate extension of the diallel-cross analysis, estimates were obtained for the phenotypical, environmental, and genetical correlations between the phenotypes studied. A factor analysis performed on the matrix of additive-genetic correlations revealed that variations in the size of the intra- and infrapyramidal mossy fiber terminal fields (iip-MF) are negatively related to open-field exploration and novelty-induced fear. These results indicate that having larger iip-MF projections promotes the collection and processing of information about a novel environment, entailing lower levels of exploration and fear.

Animals↗

Behavioral consequences of radiation exposure to simulated space radiation in the C57BL/6 mouse: open field, rotorod, and acoustic startle.

Two experiments were carried out to investigate the consequences of exposure to proton radiation, such as might occur for astronauts during space flight. C57BL/6 mice were exposed, either with or without 15-g/cm2 aluminum shielding, to 0-, 3-, or 4-Gy proton irradiation mimicking features of a solar particle event. Irradiation produced transient direct deficits in open-field exploratory behavior and acoustic startle habituation. Rotorod performance at 18 rpm was impaired by exposure to proton radiation and was impaired at 26 rpm, but only for mice irradiated with shielding and at the 4-Gy dose. Long-term (>2 weeks) indirect deficits in open-field activity appeared as a result of impaired experiential encoding immediately following exposure. A 2-week recovery prior to testing decreased most of the direct effects of exposure, with only rotorod performance at 26 rpm being impaired. These results suggest that the performance deficits may have been mediated by radiation damage to hippocampal, cerebellar, and possibly, forebrain dopaminergic function.

Animals↗

Differential modulation of hippocampal signal transfer by tuberomammillary nucleus stimulation in freely moving rats dependent on behavioral state.

Tuberomammillary histamine neurons (TM) in the posterior hypothalamus project to extensive parts of the brain, including the hippocampal formation. The purpose of the present experiments was to investigate whether activation of the TM modulates signal transfer from the perforant pathway (PP) or ventral hippocampal commissure (VHC) to the dentate gyrus (DG) in freely moving rats. Paired pulses of electrical stimulation were delivered to PP or VHC, and evoked field potentials (fEPSPs and pop spikes) were recorded in the DG. Before activating PP or VHC, the TM was triggered by electrical stimulation. Experimentation was performed during four behavioral conditions: exploration, grooming, awake immobility, and slow-wave sleep. Electrical activation of the TM was found to modify dentate fEPSPs evoked by PP or VHC stimulation without generating a field potential by itself. Train stimulation of the TM (100 Hz, 500 ms) preceding paired pulses on the hippocampus by 50 ms decreased dentate fEPSPs in dependence of the ongoing behavior and the pathway stimulated. During exploration but not consummatory behavior, the PP signal was reduced when preceded by TM stimulation; during consummatory behavior but not exploration, the VHC signal was reduced. In contrast to other hippocampal afferents which increase pop spikes but leave fEPSPs unchanged, TM stimulation decreased dentate fEPSPs without affecting pop-spike activity. Thus, the TM-histaminergic system seems to modulate signal processing in the dentate gyrus in a specific way, exerting an inhibitory action on the entorhinal input only during learning-related exploratory behavior.

Animals↗

Differential effects of handling on exploration in male and female rats.

In this study, sex differences in the exploratory behavior of handled and nonhandled animals were measured under conditions of both high and low stimulus variation. The apparatus used was a hole-board, which provided an exploratory response independent of ambulation. Significant effects of handling were found: nonhandled animals decreased head-dipping over days whereas handled animals maintained a high rate. Sex differences were also observed: patterns of head-dipping for males and females differed over days depending on whether objects was present (high stimulus variation) or absent (low stimulus variation) under the hole-board; females also head-dipped for longer durations than males when objects were present; further, males and females showed completely opposite patterns of exploration depending on handling treatment and on level of stimulus variation. We conclude that handling differentially affects males and females, particularly as level of stimulus variability changes.

Animals↗

Carbamazepine enhances discriminative memory in a rat model of epilepsy.

PURPOSE: Seizures and antiepileptic drugs (AEDs) are the main causes for cognitive impairment in persons with epilepsy. It is still a matter of debate whether carbamazepine (CBZ) improves cognition because of its own psychotropic effects or because it is more effective to treat temporal epilepsy. Our objective was to analyze the performance of CBZ-treated or nontreated pilocarpine epileptic rats in an object-recognition test. METHODS: Twelve chronic pilocarpine-induced epileptic rats were treated with CBZ, 40 mg/kg, or saline, t.i.d. for 8 days. Twenty-one nonepileptic controls were treated with CBZ or saline. On day 8 of treatment, all rats were tested with an object-recognition paradigm. RESULTS: No locomotor impairment was detected in chronic epilepsy or CBZ treatment, as exploration during training was not affected. Exploratory behaviors during the choice session were not decreased in rats treated with CBZ; therefore CBZ does not compromise procedural memory. Epileptic rats showed a nonsignificant change in the discrimination performance, and prolonged treatment with CBZ in epileptic rats induced a significant increase in object discrimination during the choice session. CONCLUSIONS: Even though pilocarpine-induced epileptic animals do not show compromised performance in the spontaneous object-recognition test, prolonged CBZ treatment has a positive effect on a simple object-discrimination task. These results may be associated with the psychotropic effects of CBZ.

Animals↗

Computerized analysis of audible and ultrasonic vocalizations of rats as a standardized measure of pain-related behavior.

The behavioral assessment of experimental pain is essential for the analysis of pain mechanisms and the validation of therapeutic targets. Arthritic pain, in particular, is significantly associated with negative affective states and disorders. Here we present a standardized method for the quantitative analysis of audible and ultrasonic (25 +/- 4 kHz) vocalizations in awake rats as a measure of higher integrated behavior in a model of arthritic pain. A bat detector and a condenser microphone were used to record ultrasonic and audible vocalizations, respectively, in response to innocuous and noxious mechanical stimulation of the knee before and after induction of acute arthritis in one knee. A computerized system was used to analyze number and duration of the filtered signals. For the behavioral tests, the animal was placed in a customized recording chamber to ensure consistent stimulus application and stable recordings and to eliminate any movement-induced noise. Noxious stimuli produced stronger vocalizations than innocuous stimuli. Both audible and ultrasonic vocalizations to innocuous (allodynia) and noxious (hyperalgesia) stimuli increased after the induction of acute arthritis. These changes were accompanied by increased knee joint circumference, lowered hind limb withdrawal thresholds and reduced exploratory behavior in the same animals. The computerized analysis of audible and ultrasonic vocalizations is a valid, quantitative, reliable and convenient method to measure pain-related behavior.

Analysis of Variance↗